/*
 * The contents of this web application are subject to the Mozilla Public License Version 
 * 1.1 (the "License"); you may not use this web application except in compliance with 
 * the License. You may obtain a copy of the License at http://www.mozilla.org/MPL/.
 * 
 * Software distributed under the License is distributed on an "AS IS" basis, 
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License 
 * for the specific language governing rights and limitations under the License.
 * 
 * The Original Code is owned by and the Initial Developer of the Original Code is 
 * Composite A/S (Danish business reg.no. 21744409). All Rights Reserved
 * 
 * Section 11 of the License is EXPRESSLY amended to include a provision stating 
 * that any dispute, including but not limited to disputes related to the enforcement 
 * of the License, to which Composite A/S as owner of the Original Code, as Initial 
 * Developer or in any other role, becomes a part to shall be governed by Danish law 
 * and be initiated before the Copenhagen City Court ("K�benhavns Byret")            
 */

using System;
using System.Collections.Generic;
using Composite.Functions;

namespace Composite.Plugins.PageTemplates.MasterPages.Controls.Functions
{
    internal class LazyParameterRuntimeTreeNode : BaseParameterRuntimeTreeNode
    {
        private readonly Func<object> _getValueFunction;
        private object _result;
        private bool _evaluated;

        public LazyParameterRuntimeTreeNode(string parameterName, Func<object> getValueFunction)
            : base(parameterName)
        {
            _getValueFunction = getValueFunction;
        }

        public override object GetValue(FunctionContextContainer contextContainer)
        {
            if (!_evaluated)
            {
                _result = _getValueFunction();
                _evaluated = true;
            }

            return _result;
        }

        public override IEnumerable<string> GetAllSubFunctionNames()
        {
            throw new NotSupportedException();
        }

        public override bool ContainsNestedFunctions
        {
            get { return false; }
        }

        public override System.Xml.Linq.XElement Serialize()
        {
            throw new NotSupportedException();
        }
    }
}
